Conventionally, a driving apparatus including a transmission unit has been widely known. For example, in Patent Literature 1, a technique of a driving apparatus of a hybrid vehicle which apparatus includes a transmission mechanism to shift a rotation of an internal-combustion engine and to transmit the rotation to a power distribution mechanism, a first transmission shaft to transmit power from the internal-combustion engine to the transmission mechanism, and a second transmission shaft to transmit the power output from the transmission mechanism to the power distribution mechanism has been disclosed.